Localized corrosion of (lean) duplex stainless steels in immersion units of urban wastewater treatment plants

With lower alloying cost and higher mechanical properties, lean duplex stainless steels can be an alternative to the more commonly used austenitic stainless steels. However, these alloys are still not the preferred choice, probably due to a lack of field experience. A study was thus initiated in view of defining the limits of use of selected (lean) duplexes for urban wastewater treatment units. The present paper shows the localized corrosion performance of selected lean duplexes in chloride contaminated solutions. The results are compared with austenitic S30403 and S31603 and with the more standard duplexes S82441 and S32205. The effect of welding was also investigated. Exposures in field municipal wastewater plants were conducted for 1 year in low and high chloride content units. The results show that lean duplexes S32101 and S32202 can be used as alternatives to S30403 and S31603 in low chloride electrolytes. At 500 ppm of chloride content, duplex stainless steel S32304 showed better corrosion resistance than S30403 and S31603. For higher chloride contents (1000 ppm and above) the standard duplexes S82441 and S32205 shall be preferred.     

Defining Dry Eye from a Clinical Perspective

Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint.     

Triggering of cellulase biosynthesis by cellulose in Trichoderma reesei. Involvement of a constitutive, sophorose-inducible, glucose-inhibited beta-diglucoside permease

We prepared [U-14C]cellobiose by cultivating Acetobacter pasteurianus in the presence of [U-14C]glucose and hydrolyzing the [U-14C]cellulose formed with beta-glucosidase-free cellulase from Trichoderma reesei. This 14C-labeled cellobiose was used to investigate the presence of an uptake system for cellobiose in T. reesei. Evidence was obtained for the presence of a high affinity (Km for cellobiose 0.3 microM) but low activity (2.5 milliunits/mg fungal dry weight) cellobiose permease. The permease is formed constitutively, but higher levels are formed after addition of sophorose (glucosyl-beta-1,2-diglucoside), a reputed cellulase inducer. The permease appears to be specific for beta-diglucosides, as the uptake of [U-14C]cellobiose is inhibited by sophorose, gentiobiose (glucosyl-beta-1,3-glucoside), and cellobiose. Under these conditions, cellooligodextrines (n, 4-7; final concentration, 1 mM) are not inhibitors. Glucose, but no other monosaccharides, inhibits the permease. The hypersecretory mutant T. reesei RUT C-30 exhibits elevated permease activities, whereas in T. reesei QM 9979, a mutant strain defective in the induction of cellulases by cellulose or sophorose, strongly reduced permease activities were demonstrated. The results stress a hitherto not recognized point of control in the induction of cellulases by T. reesei at the level of uptake of cellulose oligosaccharides.     

Cortisone-induced osteoporosis: effects on bone adenylate cyclase

The majority of patients with soft tissue or bone sarcomas of the upper extremity can be treated today with limb-saving procedures using combined modality therapies. For patients with a tumor in the shoulder area, sometimes an interscapulothoracic amputation is the only radical surgical treatment. However, in selected cases, in which the tumor does not involve the neurovascular bundle, a limb-sparing alternative might be the Tikhoff-Linberg resection. Normal function of the hand and forearm, with reasonable function of the elbow, can be maintained by this procedure. Four case histories are reported.     

Stress Heterogeneity Effect on the Strength of Silicon Nitride

The experiments reported in this paper demonstrate the causes of the failure of monolithic ceramics. The specimens are made of silicon nitride and tested at room temperature. The stress field within the specimen is different for each of four series of tests that have been conducted. Fractographic observations have also been made to identify the causes of the failures. A size effect analysis is performed.     

Construct validity of WAIS—R factors: Neuropsychological test correlates in adults referred for evaluation of possible head injury.

A 3-factor solution of the Wechsler Adult Intelligence Scale—Revised (WAIS—R; Wechsler, 1981) in 260 adults with suspected head injury suggested relatively good construct validity for the factors, based on correlations with neuropsychological tests purported to measure similar abilities. The Verbal Comprehension factor was related to verbal ability, verbal memory, and executive functioning. The Perceptual Organization factor, although measuring primarily visual–spatial perception and visual constructional ability, was related to visual–spatial memory, visual attention, and executive functioning. The Freedom From Distractibility factor was correlated with two attention measures and was not associated with memory measures. Its association with executive functioning was inconsistent. The findings are discussed in terms of the multidimensional nature of neuropsychological tests and WAIS—R factors. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

PRA as a management tool: organizational factors and risk-based priorities for the maintenance of the tiles of the space shuttle orbiter

A probabilistic risk assessment (PRA) model, developed for the Thermal Protection System (TPS) of the space shuttle orbiter and presented in the previous paper, is used as a management tool to identify root-cause, organizational factors of the various failure modes. The objective is to set priorities in the process of resource allocation to minimize the risk of accident caused by the failure of the TPS. Starting with the technical characteristics of the system and the inputs of the risk assessment model, the approach is to identify the human decisions and actions and the key organizational factors that influence the risk.

Among the management factors that affect the reliability of the TPS are time pressures that have occurred in the past, liability concerns and conflicts among contractors, the low status of the tile work and material technicians among maintenance personnel, the absence of priorities in tile testing, and under-recognized couplings among subsystems (such as the external tank insulation as a source of debris that may hit the tiles). It is shown here how using the PRA results to set priorities in the maintenance of the tiles can allow reduction of the overall risk, and how critical zones of debris sources can be identified on the surface of the external tank and the solid rocket booster. It was found, for instance, that detecting and fixing loose tiles in the most risk-critical areas and securing insulation by up to 80%, and securing the insulation of external systems in specified areas could reduce the TPS risk by about 75%.     

Where is the infant in infant intervention? A review of the literature on changing troubled mother-infant relationships.

Four intervention models that aim to reduce problematic caregiver–infant relationships are reviewed within the context of attachment theory. These models include support, guidance, psychotherapy, and infant-led psychotherapy. All of the models are consistent with attachment theory in that they aim to enhance maternal sensitivity and responsiveness. Only infant-led psychotherapy focuses primarily on the mother–infant relationship and directly includes the infant in treatment instead of focusing and working primarily with the more verbal partner, the caregiver. Thus, of the 4 interventions, infant-led psychotherapy is most consistent with the current empirical and theoretical understanding of infants as active contributors to their relationships and development. However, there is little empirical research on this intervention; the bulk of studies evaluate support and guidance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)